Mixed ureas



Patented Dec. 31, 1940 PATENT OFFICE MIXED UREAS Alfred Rohm,Leverkusen-I. G. Werk, Germany, assignor to General Aniline & FilmCorporation, New York, N. Y., a corporation of Delaware No Drawing.Application January 18, 1940, Se-

rial No. 314,453. In Germany January 24,

4 Claims.

The present invention relates to mixed ureas containing solubilizinggroups and to a process of preparing the same.

In my copending application Ser. No. 304,177, filed November 13, 1939,entitled Mixed ureas a process for the manufacture of mixed ureascontaining solubilizing groups is described. This process consists inallowing O-aryl-urethanes of Watersoluble amines to react in aqueoussolution with primary or secondary aliphatic or aromatic amines whichmay be further substituted and which may or may not contain solubilizinggroups.

I have now found that mixed Watersoluble ureas can also be obtained byallowing waterinsoluble O-aryl-urethanes to react with aqueous solutionsof primary or secondary aliphatic or aromatic amines containing at leastone watersolubilizing group, if carrying out the reaction in thepresence of an organic solvent for the said urethanes. This synthesis isjust as generally applicable as the synthesis described in my copendingapplication and is performed under similar conditions, i. e. thetemperature at which the reaction is carried out may vary in widelimits; the reaction is mostly performed at a pH of about 7 to 8, the pHvalue may, however, be shifted to the acid or alkaline side. The yieldsare likewise very good. The mixed watersoluble ureas obtained accordingto the new process are in some cases also obtainable according to theknown isocyanate process, however, in' lower yields. In many cases,however, it is not at all possible, to prepare the isocyanate necessaryWhereas the O-aryl-urethanes are quite generally obtainable withexcellent yields.

The amine portion of the O-aryl-urethanes may be derived from primary orsecondary aliphatic or aromatic amines, free from watersolubilizinggroups; these amines may be monamines or diamines. As primary orsecondary aliphatic aromatic amines with at least one watersolubilizinggroups any of the amines of this group may be used; by way of example afew of these amines may be mentioned: amino-acetic acid, aminoethanesulfonic acid (taurine), methylaminoethane sulfonic acid(methyltaurine), the aminobenzene sulfonic acids, the phenylene diaminesulfonic acids, the aminobenzoic acids, the aminosalicylic acids, theaminodiphenyloxide sulfonic acids, the aminonaphthalene sulfonic acids,the aminohydroxy-naphthalene sulfonic acids and the correspondingsecondary amines in which e. g. one hydrogen atom of the amino group isreplaced by alkyl or aryl. Also in this process it is in most casesexpedient to employ the amine in excess in order to use up the urethaneas completely as possible.

The watersoluble mixed ureas obtained according to the new process arevaluable intermediates for the preparation of dyestuffs or are alreadydyestuffs themselves.

The following examples illustrate the invention without, however,limiting it thereto.

Example 1 15.1 g. (=0.1 mol) of .1-amino-4-acetaminobenzene aresuspended in 100 cc. suspension and 16 g. of phenyl chloroformate aradded drop by drop while stirring. The hydrogen chloride formed is fixedby the addition of 0.1 mol of a tertiary base, for instancedimethylaniline or by the addition of an aqueous solution of aninorganic base. This mixture containing the phenylurethane of1-amino-4-acetaminobenzene is add ed to a solution of 0.1 mol of thesodium salt of 2-amino-5 hydroxynaphthalene-7-sulfonic acid in 400 cc.of water, brought to pH 7.5 and slowly warmed with stirring untilsolution has become complete. When the diazotization value of thesolution no longer decreases the reaction is complete. The phenol isdistilled off with steam from the acidified solution and the mixed ureaof 2- amino 5 hydroxynaphthalen-7-su1fonic acid and1-amino-4-acetaminobenzene is isolated in very good yield by addingsodium chloride. This urea can not be produced by the isocyanateprocess, since the corresponding isocyanate cannot be prepared.

Instead of 2-amino-5-hydroxynaphthalene-7- sulfonic acid2-amino-8-hydroxynaphthalene-6- sulfonic acid can be employed in thesame way. In an analogous manner the O-aryl-urethanes of other amineswithout watersolubilizing groups, for instance of theI-amino-benzenel-sulfamide can be converted into mixed soluble ureas byallowing these urethanes to react with the aqueous- Example 2 10.8 g.(=01 mol) of 1.4-diaminobenzene are dissolved in 100 cc. of dioxane andare converted into the di-phenyl-urethane of the 1.4-diaminobenzene byadding 32 g. of phenyl chloroformate and 35 g. of dimethylaniline. Tothis mixture the solution of 0.22 mol of the sodium salt of 2-amlno-S-hydroxynaphthalene-7-sulfonic acid in 500 cc. of water is added,the mixture is brought to pH 7.5 and refluxed until solution iscomplete.- Now the solution is rendered alkaline with sodium carbonateand the dimethylaniline is distilled oil with steam. Thereupon themixture is rendered acid with acetic acid and the phenol is driven offby steam. On cooling the di-(zamino-5-hydroxynaphthalene-7-sulfonicacid)- urea oi the 1.4-diaminobenzene separates from the solution andcan be 'purifled by redissolving. Instead of2-amino-5-hydroxynaphthalene-7- sulfonic acid a corresponding quantityof 2- aminonaphthalene-5-sulfonic acid may be used whereby in the sameway the corresponding diurea is obtained.

In a similar way other diamines or the substitution products thereof,such as ethylenediamine, 4.4'-diaminodiphenyl and others may beconverted into di-ureas in the presence of suitable solvents.

I claim:

1. Process for the preparation of mixed ureas containing solubilizinggroups from waterinsoluble urethanes of the general formula:

wherein R stands for an aromatic radical, R stands for a radicalselected from the group consisting of aliphatic and aromatic radicalsfree from solubilizing groups, and X stands for one of the groupconsisting of hydrogen, alkyl and aryl, which process consists inallowing the said urethanes to react with aqueous solutions of aminesselected from the group consisting of primary and secondary aliphaticand aromatic amines containing at least one watersolubilizing group inthe presence of an organic solvent for the said urethanes.

2. Process for the preparation of mixed ureas containing solubilizinggroups from waterinsoluble urethanes of the general formula:

R-O.CO.II\IR wherein R stands for an aromatic radical, R

stands for a radical selected from the group consisting of aliphatic andaromatic radicals free from solubilizing groups, and X stands for one ofthe group consisting of hydrogen, alkyl and aryl, which process consistsin allowing the said urethanes to react with aqueous solutions of aminesselected from the group consisting of primary and secondary aliphaticand aromatic amines containing at least one watersolubilizing group atmedium pH values in the presence of an organic solvent for the saidurethanes.

3. Process ior the preparation 01 mixed ureas containing solubilizinggroups from waterlnsoluble urethanes oi the general formula:

wherein R stands for an aromatic radical, R stands for a radicalselected from the group consisting of aliphatic and aromatic radicalsfree from solubilizing groups, and X stands for one of the groupconsisting of hydrogen, alkyl and aryl, which process consists inallowing the said urethanes to react with aqueous solutions of aminesselected from the group consisting of primary and secondary aliphaticand aromatic amines containing at least one watersolubilizing group atpH values of about 7 to about 8 in the presence of an organic solventfor the said urethanes.

4. Process for the preparation of mixed ureas containing solubilizinggroups from waterinsoluble urethanes of the general formula:

wherein R. stands for an aromatic radical, R stands for a radicalselected from the group consisting of aliphatic and aromatic radicalsfree from solubilizing groups, and X stands for one of the groupconsisting of hydrogen, alkyl and aryl, which process consists inallowing the said urethanes to react with aqueous solutions af aminesselected from the group consisting of primary and secondary aliphaticand aromatic amines containing at least one watersolubilizing group atpH values of about '7 to about 8 and at temperatures between about roomtemperature and the boiling point of the solutions in the presence of anorganic solvent for the said urethanes.

ALFRED ROHM.

